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authorDavid Rowley <drowley@postgresql.org>2024-03-15 11:54:36 +1300
committerDavid Rowley <drowley@postgresql.org>2024-03-15 11:54:36 +1300
commit4169850f0b6fc98a5f28d2b0ca4c3a4c1ecf4553 (patch)
tree31f98e96b56888e8c09dfed9f139de94b4ef7add /src
parent4665cebc8a01dabd54b000bcc107a3468be3a81c (diff)
downloadpostgresql-4169850f0b6fc98a5f28d2b0ca4c3a4c1ecf4553.tar.gz
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Trim ORDER BY/DISTINCT aggregate pathkeys in gather_grouping_paths
Similar to d8a295389, trim off any PathKeys which are for ORDER BY / DISTINCT aggregate functions from the PathKey List for the Gather Merge paths created by gather_grouping_paths(). These additional PathKeys are not valid to use after grouping has taken place as these PathKeys belong to columns which are inputs to an aggregate function and, therefore are unavailable after aggregation. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/cf63174c-8c89-3953-cb49-48f41f74941a@gmail.com Backpatch-through: 16, where 1349d2790 was added
Diffstat (limited to 'src')
-rw-r--r--src/backend/optimizer/plan/planner.c19
1 files changed, 15 insertions, 4 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 443ab08d75a..5564826cb4a 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -7320,6 +7320,17 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
{
ListCell *lc;
Path *cheapest_partial_path;
+ List *groupby_pathkeys;
+
+ /*
+ * This occurs after any partial aggregation has taken place, so trim off
+ * any pathkeys added for ORDER BY / DISTINCT aggregates.
+ */
+ if (list_length(root->group_pathkeys) > root->num_groupby_pathkeys)
+ groupby_pathkeys = list_copy_head(root->group_pathkeys,
+ root->num_groupby_pathkeys);
+ else
+ groupby_pathkeys = root->group_pathkeys;
/* Try Gather for unordered paths and Gather Merge for ordered ones. */
generate_useful_gather_paths(root, rel, true);
@@ -7334,7 +7345,7 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
int presorted_keys;
double total_groups;
- is_sorted = pathkeys_count_contained_in(root->group_pathkeys,
+ is_sorted = pathkeys_count_contained_in(groupby_pathkeys,
path->pathkeys,
&presorted_keys);
@@ -7360,13 +7371,13 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
*/
if (presorted_keys == 0 || !enable_incremental_sort)
path = (Path *) create_sort_path(root, rel, path,
- root->group_pathkeys,
+ groupby_pathkeys,
-1.0);
else
path = (Path *) create_incremental_sort_path(root,
rel,
path,
- root->group_pathkeys,
+ groupby_pathkeys,
presorted_keys,
-1.0);
@@ -7375,7 +7386,7 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
rel,
path,
rel->reltarget,
- root->group_pathkeys,
+ groupby_pathkeys,
NULL,
&total_groups);